A directive of European Convention on Human Rights requires Member States to
make a choice between banning completely direct marketing calls to
"subscribers" without their prior consent, or banning them only to
"subscribers" who do not wish to receive such calls.

The UK took the later route and made compliance with the UK Corporate Telephone
Preference Service mandatory. This apparently also applies to calls to
businesses.

United States

Please see the numerous listings relating to GLBA, HIPPA, and TCPA. In
many cases "automatic" privacy is not provided for under US law and
therefore the individual must "opt-out" of having data used for other
than the explicit purpose for which the data was given.

47 CFR § 222 -
"Privacy of customer information" - This is a little-publicized law
that prevents access to individually identifiable customer information for
marketing purposes. This law dates back to 1934, but was updated to include
"location" information (GPS and cellular based e-911 data).

This law will become increasingly important as carriers must seek permission
prior to delivering targeted advertisements, in part because of the requirement
to display "unique view hits" or account data. If this law is
enforced, such targeted advertisements may be used, but only if they are
optional as part of a payment scheme.

Their emphasis is to refuse to participate at all. My opinion is that
these customer tracking cards are presently causing more harm to the
supermarkets that use them, and that bogus data is better than no data.

In some cases, identification is required. Most of the ones that require
identification do so for cheque cashing purposes, so it is likely they have a
procedure for non-verified cards without check cashing privileges.

Using the DMA Mail Preference Service (DMA Choice)

... and a reason to never give a business or organisation a direct
email address

U.S. Postal Service Prohibitory Orders (Form 1500,
US only)

A U.S. Postal Service Form 1500 Prohibitory Order is used to block
commercial mail that the recipient finds offensive.

NOTE: Form 1500 describes "sexually oriented
advertisements", but the US Supreme Court
(Rowen v. USPS, 397 US 728 (1970)) stated this
applies to all unwanted commercial mail. Regardless, the USPS never
changed the wording of Form 1500, in order to discourage citizens from
filing these Prohibitory Orders. The form may be submitted to a local post
office manager or to the mail address listed on the form.